Slidable abutment rotary pump



Get. 26, 1948. J JOHNSON 2,452,467

SLIDABLE ABUTMENT ROTARY PUMP Filed Dec. 1, 1942 I 3 Sheets-Sheet 1INVENTOR. Jkmss F/Zmvsow Oct. 26, 1948. J. P. JOHNSON SLIDABLE ABUTMENTROTARY PUMP 5 Sheets-Sheet 2 Filed Dec. 1, 1942' INVENTOR.

Oct. 26, 1948. JOHNSON 2,452,467

Filed Dec. 1, 1942 SLIDABLE ABUTMENT ROTARY PUMP 3 Sheets-Sheet 5 IN VEN TOR.

claws R Jamwsow Patented Oct. 26, 1948 ZASZABF STATES P'ihNT r'icsSLIDABLE ABUEMEN '1 ROTARY PUMP James P. Johnson, Shaker Heights, GhioApplication December 1, 1942, Serial No. 467,510

17 Claims. (Cl. 103123) This invention relates to rotary pumps and moreparticularly to small capacity pumps especially adaptable for use onaircraft, in delivering, under suitable pressure, anti-icing fluid toslinger rings on propellers although its construction lends itself toother uses obvious to those skilled in the art.

This application is a continuation in part of my co-pending applicationSerial No. 360,630, filed October 10, 1940, now abandoned.

An object of the present invention is to provide a pump of the typereferred to having a non-circular rotor cooperatively associated with arelatively non-rotatable .blade or vane, the latter being mounted forreciprocatingmovemerit and actuated by the rotor to minimize the number.of moving parts.

Another object of the present invention is to provide a rotary pumphaving a fluid inlet opening and a pair of outlet openings, with pumpingmeans so arranged as to meter and discharge the incoming fluid in equalquantities and at .equal pressures from both .ou'tle't openings,

Another object of the invention is to provide a rotary pump of the typereferred to in which the number of inlet openings and the number ofoutlet openings may be varied relatively to .adapt the pump to differentconditions.

Another object of the present invention is to provide a rotary pump, thecapacity of which may be varied within definite limits in 'a quick andsimple manner depending upon the requirements.

Another object of the present invention is to provide a removable insertheld in operative posit-ion Joy a cover member and in which the rotor,blades, and porting are so positioned relattvelytha't production andassembly are materially simplified as well as effecting increasedeniciency in operation.

Another object of the present invention is to provide a rotary pump ofthe type referred to which is simple in construction, eflicient inoperation, and inexpensive to manufacture and assem'ble.

With the objects above indicated, and other "objects hereinafterexplained in View, my invention consists in the construction andcombination of elements hereinafter described and claimed.

- Referring to the drawings:

Figure 1 is a side elevational view of a rotary pump embodying thepresent invention, the same being driven by an electric motor.

Figure '2 is a transverse sectional view taken Cir 2 along .line 2-2 inFigure 1 and showing details of the pump chamber,

Figure 3 is a -vertical sectional view taken on line 3-4 in Figure l andshowing further details of the pump structure.

Figure 4 is a fragmentary transverse sectional view taken on line i-4 inFigure 2 and showing further details of the pump embodying the presentinvention. v

Figure 5 is a fragmentary transverse sectional view taken on line 5-5 inFigure 2 and showing further details of the pump.

Figure 6 is a fragmentary plan view .showing the contour of the rotorand the cooperating blade on an enlarged scale.

Figure 7 is a transverse sectional view .taken substantially along linel! in Figure 8 and showing a modfied form of the rotary pump.

Figure 8 is a fragmentary vertical sectional View taken substantiallyalong line 8-8 in Fig- .ure 7 and showing further details of the samemodification.

Figure 9 is a fragmentary side elevational view, in full scale, of afurther improved rotary :lluid metering pump embodying the invention,partly in section to more clearly illustrate the structural features.

Figure 10 is a transverse sectional view taken substantially along lineill-l0 in Figure 9 and on double scale to show more accurately therelative size and disposition of the ports, blades, etc.

Figure 11 is a fragmentary transverse sectional view in full scale,taken in a central plane through the fluid inlet opening as illustratedin Figure 9, and showing the manner of effecting communication betweenthe pump chamber and inlet opening.

Figure 12 is a fragmentary transverse sectional view in full scale,taken in a central plane through both outlet openings as illustrated inFigure 9 and showing the manner of effecting communication betweenthe-pump chamber and both outlet openings. v

Figure 13 is a fragmentary end elevational view, at 5 times the normalscale, of the removable insert of Figure 9 and showing the contour ofthe-pump chamber bore, the shape and d'is position of the adjacent inletand outlet ports, and the intermediate slots for the blades,

In the drawings I have illustrated an antiicing pump embodying thepresent invention, positively driven by means of an electric motor whichis the customary manner for effecting rotation of the pumping means butthe invention may be otherwise adapted as will be obvious to thoseskilled in the particular art.

The pump and driving means are shown in full scale in the accompanyingdrawings in order that its size and compactness may be visuallyappreciated but the size may be varied to meet whatever conditions arerequired. The pump comprises a housing I9, preferably a bronze castingor other similar material, which has a bore ll extending inwardly fromone end thereof terminating in a transversely extending inner wall l2.The housing In is provided with a fluid inlet opening l3 and a pair offluid outlet openings i4 and I5 respectively in communication with apumping means to be later described.

A cover [6, likewise preferably a bronze casting or other suitablematerial, normally closes the open end of the housing and has alaterally extending marginal flange I1 engageable with the adjacent faceof the housing and removably connected thereto by a plurality of boltsIS. A gasket I9 is disposed between the adjacent faces of the housingand flange to provide a fluid tight seal. The cover l6 has an annularextension 20 projecting inwardly in the bore and the inner face of theannular extension is in abutting eng agement with the adjacent portionof the inner wall l2 thus providing an enclosed pump chamber 2| as moreclearly shown in Figure 3.

A rotor 22, of tool steel or similar material, is rotatably disposedconcentrically within the pump chamber 2| and has its opposite ends inrunning engagement with the adjacent walls of the housing and cover. Theperipheral surface of the rotor 22 is of non-circular shape andpreferably in the form of a three lobe cam with elevations 23 rotatablyengageable with the inner peripheral wall of the pump chamber as moreclearly shown in Figs. 2 and 6, the fluid completing an adequate seal.The depressions 24 are positioned diametrically opposite to theelevations '23, and thus, as shown, as the radius of elevation 23 comesto its maximum, the radius of depression .24 opposite comes to itsminimum compensatively, and theoverall diametral measurement isuniformly the same at all diameters passing through the axis of rotationof the rotor, or otherwise stated, the diameter is a constantthroughout. The rotor thus provides three non-communicating fluidchambers 26 between the elevations 23.

A blade assembly comprising a unitary assembly of two blades integrallyjoined to each other in the form of a member 21, of tool steel orsimilar material, is relatively long and thin having laterally extendingends 23 spaced relatively in substantially parallel relation the inneradjacent faces being at 29 for running engagement at diametricallyopposite sides of the peripheral surface of the rotor 22 whereby theblade 21 is reciprocated. As the diameter of the rotor is uniformthroughout, the rotor makes a running fit with the blade in allpositions. The blade member 21 is slidably but nonrotatably mounted in acorrespondingly shaped groove '20 formed in the adjacent portion of thecover 16 and the ends 28 are slidably disposed in slots 3| formed in theadjacent annular flange 20 between inlet and outlet openings, as moreclearly shown in Figure 2.

Communication is afiorded between the fluid outlet opening [4 and thepump chamber 2| by an opening 32 provided in the adjacent flange 2K0 onone side of the blade 30, and between the fluid outlet opening l and thepump chamber by an opening 33 provided in-the adjacent flange 21) butdiametrically opposite and on the opposite side of the blade as moreclearly shown in Figure 2.

To establish communication between the fluid inlet opening l3 and thepump chamber 2!, openings 34 and 35 are provided in the flange 20 ondiametrically opposite sides and each opening is disposed on theopposite side of the blade 30 from its adjacent outlet opening 32 and 33respectively as more clearly shown in Figure 2. Due to the fact thatonly one fluid inlet opening I3 is desired the openings 34 and 35 shouldbe suitably connected and, in the present instance, an annular groove 36is formed on the peripheral wall of the bore ll, encircling the annularextension 20, and in common communication with the openings 34 and 35and the fluid inlet opening l3 as more clearly shown in Figures 2, 3, 4and 6.

It should be here pointed out that if two fluid inlet openings aredesired the annular groove 36 should be eliminated and the openings 34and 35 each connected directly with the different fluid inlet openingssimilar to the one indicated by the numeral l3. On the other hand shouldone fluid inlet opening and one fluid outlet opening be desired anadditional annular groove similar to the one indicated by the numeral36, should be provided it being located on the peripheral wall of thebore ll, but spaced inwardly from the groove 36. The additional grooveshould be in common communication with the openings 32 and 33 affordingcommunication with a single fluid outlet opening or one of the outletopenings M or 15 should be plugged.

In operation, referring particularly to Figure 2, as the rotor 22rotates in the direction of the arrow, fluid is drawn in through theinlet opening 13, flows around the groove 35, and through the openings34 and 35 respectively, the fluid being drawn successively into thenon-communicating fluid chambers 26. As the fluid chambers change theirrespective positions, the fluid is discharged through the outletopenings 32 and 33 depending upon which of the fluid chambers is incommunication with the outlet openings and as the fluid chambers passthe inlet openings 34 and 35 additional fluid is drawn thereinto and theoperation continues so long as the pump operates, During rotation of therotor 22 the blade 30 is reciprocated, back and forth, by reason of thenon-circular shape of the rotor and the ends 28 cooperate with the rotorin such a manner as to prevent any flow of fluid between adjacent outletand inletopenings. Due to the fact that the outlets are of identicalrelative displacement and by reason of their displacements beinggoverned by the same cam and same clearances, the discharged fluid fromeach outlet is of equal proportion provided they have the sameresistance or are at the same pressure.

Any suitable means may be provided for effecting rotation of the rotor'22 but a simple and eflicient manner is illustrated in the drawingsreferring particularly to Figure 3. The rotor 22 has an outwardlyextending axially disposed stub shaft 31 rotatably mounted in an opening38 provided in the adjacent portion of the housing In, the latter havingan extension 39 provided with an inwardly extending bore 48 in coaxialrelation with respect to the stub shaft 31. The outer end of the stubshaft 31 has a non-circular reduced end 4| adapted to fit within asimilarly shaped opening in a sleeve coupling 42. A fluid seal bearingmember comprises cooperating annular sections 43 and 44 encircling theshaft 31 and fitting within the bore 40, the lower portion 43 beingseated upon the bottom of the bore while the upper portion 44 isdisposed axially inspaced relation thereto. A- flexible annular shapedpacking member 45 is disposed between sections 43 and 44 to eflect afluid seal about the rotatable shaft. A coiled spring 46 is disposedwithin the bore 40 and encircles the sleeve 42, the lower end of thespring resting upon the upper section 44 and adapted to exert a pressuresuflicient to :maintain the seal. A washer 41 is disposed at the upperend of the springand is maintained in proper position by a snap ring 48which fits in an annular groove formed on the inner pe- "ripheral wallof the extension 39.

In the present case, the .rotor 22 is driven by means of an electricmotor 49 adapted to be mounted on the air-plane on a suitable supportingstructure and connected in an electrical circuit in any wellknowrrmanner. The circuit should include a rheostat for controlling thespeed of the electric motor so. that the speed or the rotor may belikewise, controlled. The electric motor 49 is connected through a gearreduction mechanism 50 the details of which need not be shown orexplained as any gear reduction may be used depending upon the relativespeeds desired between the electric motor and the pump rotor. Th gearreduction mechanism 50 has an outwardly extendingstub shaft M, ofnon-circular shape, adapted to fit within a similarly shaped opening inthe outer end of the sleeve coupling .42. It will be apparent from thisconstruction that the rotor will be rotated at the desired speed whichmay be controlled within-limits by suitable operation of the rheostat.This is quite important where-the pump is to be used as an anti icingpump for slinger rings and, the like onpropellers inasmuch as thequantity of anti-icing fluid required may be as little as one-halfgallon per hour and might be as much as two gallons per hour. Under.certain conditions, it would alsov be possible to connect the rotorshaft 31 directly with the electric motor where the speed of the lattercan be controlled for eifecting rotationtof the pump rotor for supplyingthe small quantity of fluid required. The pump-housing id may besuitably mounted on the electric motor housing by means of a bracket 51removably connected to both and this bracket preferably has openings :52adapting the same for securement on any suitable supporting. structure.1

The pump structure will operate very efficiently forhigh speeds as wellas fairly :high pressures,

dueto the fact that the-only reciprocating part of the pump is its lightblade. The pump, may also be used for oil and-fuel throughout theairplane where simple structures are desired. It may also be used as ahydraulic motordue to the-balanced condition of the rotor and thefactthat the inlets and outlets-are. diametrically opposite each other'thustaking most of the load off ofthe bearing, and may thus do away withcramping condiv tions so common inhydraulic motors of the r-otar-y desin.

In Figures 7 and 8 a modified form of the blade assembly is shown toassure proper running engagement between the opposite ends of the bladesandthe adjacent face of the rotor in-the event inner adjacent wall ofthe bore l l in the housing. The extension 53 is'slotted atdiametrically opposite sides, as shown in Figure 7, to receivea bladeassembly comprising a pair of blades 55 adapted for'reciprocatingmovement transversely, the inner faces of the blades being engageablewith adjacent portions of the rotor, and to join the blades and effectcontact between the blades and rotor an arcuately shaped spring 56 isdisposed in :encircling relation with respect to the extension '53 andhas its opposite ends securely connected to the outer ends of theadjacent blades in such a manner as to afford unitary movement. If thecam face is laid out correctly, i. e. with its overall cliametralmeasurement uniformly the same at all diameters passing through the axisof rotation of the rotor, there will be no variationin engagement of theblades against the wall of the pump chamber, and the spring 56 willoscillate together with the blades 56 as a unit and the spring will notflex. Therefore, the force with which the blades engage the rotor iseffected byv desirably pre-loading the spring 55. If there-should be anerror in the cam face of the rotor, the springwill flex only in theamount of error tomaintain the blades in proper engagement with the camface. The positions of the ports are :not shown in these views due tothe fact that they bear the same relationshipwith respect to the blades.aswthcse shown in Figure 2, a detailed description of which has beenhereinbefore'set forth.

In Figures 9 to 13 inclusive, a further improved rotary fluid meteringpump is illustrated which forms the subject matter of this continuingapplication. This pump structure comprises a housing 58, of aluminum orsimilar material,.having a circular bore 6! extending inwardly from oneend thereof which communicates with an axial opening 62 of relativelysmaller diameter. The outer end of the housing is provided with anoutwardly projecting marginal flange 63 to which a cover member fi4i5removably connected by a plurality of machine screws 65 or othersuitable means, for normally closing the adjacent end of the bore. Thecover member 64 is formed with a single fluid inlet opening 66interiorly threaded which extends inwardly from its outer end and a pairof substantially identical fluid outlet open: ings .61 and 5E'interiorly threaded which extend inwardly from its outer end, as moreclearly shown in Figures 11 and 12. v

A removable insert .63, of bronze or similar material, has a circularportion 10 snugly fitting within the bore 6! in the housing and anintegral stem H of relatively smaller diameter disposed in thecommunicating opening .62, the free end of the stem ill being formedwith a seat face H. The circular portion it has a pump chamber bore 12extending inwardly from its outer end which; communicates'with anopening id of relatively smaller diameter extending centrally throughthe stem .1 i. A rotor '54, of steel or similar material, is rotatablydisposed concentrically within the pump chamber bore 12 and has itsopposite faces in running enl gagement with the adjacent walls oftheinsert 69 and a bushing iii, of bronze or similar material, mounted onthe cover member 64 respectively. Th peripheral wall of the rotor '14 ispreferably, in the form of longitudinally extending elevations vorridges 16 substantially equally spaced apart relativelyin angularrelation of degrees and in.- tervening-depressions ll of small butsubstantially equal volumetric capacity, the ridges being rotatablyengageable with the inner peripheral wall ol? .t r m ham b as me eearl'reeq i in Fig. 13, the fluid completing an adequate seal. Thedepressions H are positioned diametrically opposite to the elevations orridges l6, and thus, as shown, as the radius of elevation 15 comes toits maximum, the radius of depression 11 oppo- Site comes to its minimumcompensatively, and the overall diametral measurement is uniformly thesame at all diameters passing through the axis of rotation of the rotor,or otherwise stated, the diameter is a constant throughout. The rotorthus provides three non-communicating fluid chambers 18 of small butsubstantially equal vo1- umetric capacities. The blade assembly herecomprises a pair of relatively thin steel blades 19 slidably butnon-rotatably mounted in transversely aligned slots 80 formed on theouter end of the circular portion and with their inner ends engageableat diametrically opposite sides of the peripheral wall of the rotor foreffecting reciprocation of the blades 19, the blades also being adaptedto divide the pump chamber into separate non-communicating portions, andto join the blades and effect contact between the inner ends of theblades 19 and the rotor cam face, a looped resilient spring member 8] isdisposed for free oscillatory movement in a marginal groove 82 formed atthe outer end of and on the outer peripheral wall of the circularportion 19 and has portions removably disposed in recesses 83 providedin the outer adjacent ends of the blades in such a manner as to affordunitary movement. If the cam face is formed correctly the spring member8| will oscillate together with the blades 19 as a unit and, i. e., withits overall diametral measurement uniformly the same at all diameterspassing through the axis of rotation of the rotor, there will be novariation in engagement of the blades against the wall of the pumpchamber, and the spring member will not flex. Therefore, the force withwhich the blades engage the rotor cam face is effected by desirablypreloading the spring member 8| for the same purpose as explained withreference to the modification of Figures 7 and 8.

To establish suitable communication between the single fluid inletopening and both of the pump chamber portions, the improved arrangementcomprises a pair of inlet ports 84 and 85 for the different pump chamberportions, arranged diametrically opposite and disposed relatively closeto its adjacent blade. These inlet ports 84 and 85, preferably ofsubstantially the same size, are formed on the inner peripheral wall ofthe pump chamber bore and extend parallel on opposite sides of the axisthereof, throughout the depth of the bore, the inlet ports in crosssection being of arcuate form slightly greater than a semicircle as moreclearly shown in Figures 10 and 13. At the inner end of the circularportion 69, a groove 86 of substantially uniform section, is formedonthe outer peripheral wall of the former and is in spaced relation withrespect to the groove 6 I. Inlet passageways 81 and 88 of uniformdiameter, are formed in the circular portion 69 and extend inwardly ondiametrically opposite sides from the peripheral groove 86, the innerends of the passageways communicating respectively'with the inner endsof the adjacent inlet ports 84 and 85 to afiord communication with thedifferent pump chamber portions. An inlet passageway 89 is formed in theflange 63 and has its inner end communicating with the peripheral groove86 while its outer end communicates with the single fluid inlet opening66 whereby the incoming fluid'isdivided and introduced into both pumpchamber portions successivelyas the rotor rotates.

To effect suitable communication between the pair of fluid outletopenings 61 and 68 and both of the pump chamber portions, a pair ofoutlet ports and 9-! for the different pump chamber portions, arearranged diametrically opposite and disposed relatively close to itsadjacent blade, the adjacent ports in each pump chamber portion beingrelatively spaced a distance greater than the spacing between adjacentridges to insure against direct communication. These outlet ports 90 andSI, preferably of substantially thesame size, are formed on the innerperipheral wall of the pump chamber bore 12 and extend parallel onopposite sides of the axis thereof, throughout the depth of the bore,the outlet ports in cross section being of arcuate form slightly greaterthan a semicircle as more clearly shown in Figures 10 and 13. Thebushing '15 is formed with a pair of identical outlet passageways 92 and93- so positioned relatively that their inner ends communicate with theouter adjacent ends of the outlet ports 90 and BI while their outer endscommunicate with adjacent but different fluid outlet openings 61 and 58thereby affording discharge of the fluid under pressure from both pumpchamber portions successively in substantially equal volumes uponrotation of the rotor. To prevent any trapping of the fluid dischargedthe outlet ports 90 and 9| are slotted at 92' in the direction of theadjacent blade thus providing sufliciently for the escape of fluid whichmight otherwise, affect the efliciency of the pump.

To effect rotation of the rotor 14, the latter is provided with anintegral stub shaft 93 of reduced diameter which projects axially inwardbeing rotatably but removably mounted in the central opening 13 of thestem H. The housing 60 is further, provided with a bore 94 which extendsoutwardly from its inner end, the bottom of the bore terminatingadjacent the seal face H and communicating with the opening 62. The freeend of the shaft 93 projects into the bore 94 and has a metal seal cage95 freely mounted for relative angular movement thereon, the cage beingformed with a seal face 95 engageable with the seal face H on the stem Hto afford a fluid seal. A seal ring 96, of neoprene or similar material,is secured against displacement on the inner periphery of the cage andsecurely engages the adjacent portion of the shaft in encirclingrelation to afford a shaft seal. A coil spring 91 encircles the shaftand has one end in abutment with the cage to exert sufficient force formaintaining the cooperating seal faces in sealing engagement. Theextreme free end of the shaft 93 is flattened at 98 to adapt it forremovable connection with a coupling 99 likewise, removably connected tothe end of an electric motor shaft, not shown, the electric motorindicated by the numeral I00, being suitably connected in an electricalcircuit for operating the same. The motor should be of the variablespeed type and its speed controlled preferably, by a rheostat to obtainthe best operating conditions for the metering pump.

One of the important features of the improved metering pump, shown inFigures 9 to 13 inclusive, is the ease with which the individualelements can be machined and assembled without decreasing itsefllciency. The removable insert 69 is assembled unitarily by placingthe rotor in the bore, the blades in the slots, and the preloading ringdisposed in the marginal groove with portions in the adjacent recessesof the blades. This insert, thus assembled, can be removed from 9 andreplaced in the housing bore 6| by merely removing the cover member 64in the event of injury or damage which is a simple manner of repair. Theform and arrangement of the inlet and outlet ports is, likewise,important in the simplification of production and efficiency inoperation.

In the operation of the further improvement, referring particularly toFigure 10, as the rotor H rotates in the direction of the arrow, fluid,by reason of the vacuum created, is drawn in through the single inletopening 66, flows around the communicating peripheral groove 86 on theinsert, through the communicating passageways 81, and 88 ondiametrically opposite sides, and into both pump chamber portionsthrough related communicating inlet ports 84 and 85, the fluid beingdrawn successively into the non-communicating fluid chambers 18. In asmuch as the fluid chambers 1-8 serve to transmit the fluid underpressure toeach outlet port 90 and 9| respectively, the

volume of fluid discharged is substantially equal because despite anyerrors in the rotor cam face this defect will be present in both outletsbut will haveno' detrimental efiect on the operation of the pump. As thefluid is discharged through the respective outlet ports 90 and 9! itflows through the related communicating passageways 92 and 93 and fromthem to the related communicating outlet openings 61 and 68 insubstantially equal volumes where the fluid is conveyed bysuitableconduits, not shown, to the slinger rings or simi laninstrumentalitiesto be actuated thereby.

While I' have described the preferred embodiment of the invention it isto be understood that I am: not to be limited thereto inasmuch aschanges and. modifications may be resorted to without departing from thespirit of the invention as defined in the appended claims.

What is claimed is:

1'. A rotary fluid metering pump comprising; a housing. having a pumpchamber therein, a fluid inlet. opening,v and a pair of fluid outletopenings;

a rotor rotatably disposed in said pump chamber and: having anon-circular peripheral wall in the form. of alternate ridges anddepressions so psitioned relatively to each other that the samedimension prevails between all diametrically opposite points on saidperipheral wall when passing through the axis of rotation of said rotor,said ridges being rotatably engageable with the inner peripheral wall ofsaid pump chamber and the intervening depressions being of substantiallyequal volumetric capacities; and a blade assembly slidablybutnon-rotatably mounted in said housing and having its opposite endsengageable with diametrically opposite sides of the peripheral wall ofsaid rotor for effecting reciprocation of said blade, the opposite endsof said blade dividing said pump chamber into separate non-communicatingportions; said pump being provided with a passageway affordingcommunication between said fluid inlet opening. and both of said pumpchamber portions; said pump-containing a pair of noncommunicatingpassageways each of which affords? communication between different pumpchamber portions and difierent fluid outlet openings ofsaid pair,whereby, upon rotation of said rotor, fluid is drawninto the alternatedepressions successively in both pump chamber portions fronrsaidfluidrinlet opening and" discharged under pressure in substantiallyequal volumes-from the different fluid outlet openings.

A rotary fluid metering pump comprising; a housing having a pump chambertherein, a

mean? fluid inlet opening, and a, pair ofv fluid outlet" openings; arotor rotatabl'y' disposed in said punip chamber and having anon-circular peripheral wall in the form of a three l'obecani,the'lobe's" of said cam being equally spacedapart about the axis of therotor and rotata'bly engage'abl'e with the inner peripheral wall of saidpump chamber, the surfaces of said jcam intervening between the lobesbeing spaced from" said pe iphi opposite" ends of said blade dividingsaid chamber into separate non-communicating portions; said pump beingprovided wth a assage:

way affording communication between said fluid inlet opening; and bothof said pump chamber portions; said pump containing a pair of noncommunicating passageways each of which af-' fords communicationbetween. different pump chamber portions and different fluid outlet oen: ings of saidpair, whereby, upon' rotation of saidrotor, fluid isdrawn into the intervening spaces successively in both pump chamberportions from said fluid inlet opening and discharged under pressure insubstantially equal volumes from the different fluid outlet openings;

A rotary fluid metering" pump comprising,;. a housing having a boreextending inwardly fro'm' one ndthereor; said housing having aslhglfluid inlet opening-and a; pair of fluid outlet open ing's'; a covermember at the open end of said housing for normally closing the same andremovably' connected to the latter, said cover member having' anannularextension projecting into said bore to provide with the bottom of thebore an enclosed pump chamber; a; rotor rotatabl'y disposed in said umpchamber and having. a" non-circular peripheral wall in the form of alternate ridges and depressions so positioned relatively to each other thatthe same dimension prevails between all diametrically opposite points,

on said peripheral" wall when passing through.

the axis of rotation of said rotor, said ridges being rotatablyengageable with the inner peripheral wall of said annular extension andthe intervening depressions" being of substantially equal volumetriccapacities; a blade slidably but non-rotatably mounted in said covermember and having its opposite ends engageable with diametricallyopposite sides of the peripheral wall of said rotor for effectingreciprocation of said blade the' opposite ends of said blade dividingsaid pump chamber into separate noncommunicating portions; acontinuousgroove formed on the inner peripheral. wall of said housing bore andnormally closed on its inner side by said annular extension; a pair ofsubstantially identical inlet ports in said annular extension, disposedrelatively to each other in diametrically opposite relation on oppositesides of and in close proximity to the respective ends ofsa'id' blade toaflord communication betweensaid groove and different pump chamberportions; an inlet passageway in said housing af for'ding communicationbetween said single inlet opening and said groove; a pair ofsubstantension, disposed relatively to each other in .dia-' metricallyopposite relation on opposite sides of and in close proximity to therespective ends of said blade to afford communication with differentpump chamber portions, the adjacent ports in each pump chamber portionbeing spaced apart relatively to each other a greater distance than theangular spacing of the ridges on said rotor; and outlet passageways ofsubstantially identical size in said housing each of which afiordscommunication between different outlet ports and a related outletopening, whereby, upon rotation of: said rotor, fluid is drawn into thealternate depressions successively in both pump chamber portions fromsaid single inlet opening and discharged under pressure in substan-.tially equal volumes from the different fluid out: let openings. 7

4. A rotary fluid metering pump comprising; a'housing having a, pumpchamber therein, a fluid inlet opening, and a pair of fluid outletopenings; a, rotor rotatably disposed in said pump chamber and havingnon-circular peripheral wall in the form of alternate ridges anddepressions so positioned relatively to each other that the samedimension prevails between all diametrically opposite points on saidperipheral wall when passing through the axis of rotation of said rotor,said ridges being rotatably engageable with the inner peripheral wall ofsaid pump chamber; and .a pair, of blades slidably but non-rotatablymounted in said housing and engageable at diametrically opposite sidesof the peripheral wall of said rotor for, eflecting reciprocation ofsaid blades, said blades dividing said pump chamber into separatenon-communicating portions; a looped resilient pre-loaded memberconnected to said blades for efiecting unitary movement without flexingbut adapted to maintain engagement between said blades and cam face tocompensate for slight errors in the latter with minimum flexure; saidhousing being provided with a passageway affording communication betweensaid fluid inlet'opening and both of said pump between different pumpchamber portions and different fluid outlet openings of said pair,whereby, upon rotation of said rotor, fluid is drawn successively intoboth pump chamber portions from said fluid inlet opening and dischargedunder pressure in substantially equal volumes from the different fluidoutlet openings.

5. A rotary fluid metering pump comprising; a housing having a boreextending inwardly from one end thereof, said housing having a fluidinlet opening and a pair of fluid outlet openings; a cover member at theopen end of said housing for normally closing the same and removablyconnected to the latter, said cover member having an annularextensionprojecting into said bore to provide with the bottom of thebore an enclosed pump chamber; a rotor rotatably disposed in said pumpchamber and having a non-circular peripheral wall inthe'form ofalternate ridges and depressions so positioned relatively to each otherthat the same dimension prevails between all diametrically oppositepoints on said peripheral wall when passing through the axis of rotationof said rotor, said ridges being rotatably engageable with the innerperipheral wall of said extension; a pair of blades slidably butnon-rotatably mounted in said cover member and engageable 12 withdiametrically opposite sides of the peripheral wall of said rotor foreffecting reciprocation of said blades, said blades dividing said pumpchamber into separate non-communicating portions; a looped resilientpre-loaded member connected to said blades for effecting unitarymovement without flexing but adapted to maintain engagement between saidblades and cam face to compensate for slight errors in the latter withminimum flexure; a continuous groove formed on the inner peripheral wallof said housing bore and normally closed on its inner side by saidannular extension; a pair of inlet ports in said annular extensiondisposed relatively to each other in diametrically opposite relation onopposite sides of and in close roximity to the ends of said blades toafford communication between said groove and different pump chamberportions; an inlet passageway in said housing affording communicationbetween said single inlet opening and said groove; a pair of outletports in said annular extension, disposed relatively to each other indiametrically opposite relation on opposite sides of and in closeproximity to the respective ends of said blades to afiord communicationhousing each of which affords communication be-.

cent ports in each pump chamber portion being spaced apart relatively toeach other a greater distance than the angular spacing of the ridges onsaid rotor; and outlet passageways in said tween different outlet portsand a related outlet opening, whereby, upon rotation of said rotor;

fluid is drawn into the alternate depressions successively in both pumpchamber portions from said single inlet opening and discharged underpressure in substantially equal volumes from the different fluid outletopenings.

6. A rotary fluid metering pump comprising; a housing having a boreextending inwardly from one end thereof and a single fluid inlet openingand a pair of fluid outlet openings; a cover member at the open end ofsaid housing and removably connected to the latter, said cover memberhaving an inwardly projecting annular extension snugly fitting the wallof the bore to provide with the bottom of the bore an enclosed pumpchamber; a rotor rotatably disposed in said pump chamber and having anon-circular peripheral wall in the form of alternate ridges anddepressions so positioned relatively to each other that the samedimension prevails between all diametrically opposite points on saidperipheral wall when passing through the axis of rotation of said rotor,said ridges being rotatably engageable with the inner peripheral wall ofsaid extension and the alternate depressions being of substantiallyequal volumetric capacities, said rotor being further provided with anaxially disposed driving shaft rotatably mounted in said housing; a longthin blade slidably but non-rotatably mounted in a pair of outlet portsin said annular extension,

13' disposed relatively to each other in. diametrically oppositerelation on opposite sides. of and/in, close proximity tothe respectiveends of said; blade: to afford communication with diffierent plumpcham-- ber' portions, the adjacent ports in each pump chamber portionbeing spaced apart relatively toeach other a greater distance than-theangular spacing of the ridges 'on said rotor; and outlet passageways insaid housing. each of which affords communication between differentoutlet portsand a relatedoutlet opening, whereby, upon rotation of saidrotor, fluid is drawn into the intervening' depressions successively inbothpu-mp chamber portions from said single outlet opening anddischarged under pressure in substantially equal volumes from thedifierent fluid outlet openings.

7.. A rotary fluid metering pump comprising; a housing having a boreextending inwardly fronione end thereof, and a fluid inlet open-- ing.and a pair offluid outlet openings; acover member at the open end ofsaid housing and-- removably connected to the: latter, said cover memberhaving an inwardly projecting annular extension snugly fitting the wallor the bore to provide with the bottom of the bore an enclosed pumpchamber; a rotor rota-tabl-y disposedin saidchamber. and having anon-circular peripheral wallin the form of alternate. ridges and de-"press-ions so. positioned relatively vthat the same dimension prevailsbetween all: diametrically op posite. points on said peripheral wallwhen passing through the axis. of rotation of saidroto'r, said ridgesbeing rotatably engageable with the inner peripheral wall: of saidextension and the intervening depressions being of substantially equalvolumetric capacities; said rotor beingiurther provided with an axiallydisposedidriving shaft rotatably'mounted: in said: housing; a long;vthin blade slidably but nonx-rotatabl'y mounted-- in. said cover memberand: having laterally extending opposite ends projecting into said?chamer, said-ends being engageablla with diametri cally opposite sidesof: the peripheratwal l' of said rotor-.for effectingreciprocationv offsaid blade and dividing said pump; chamber into separatenon-communication portions; said. housing being further provided with a.continuous groove-formed on the peripheral wall of the bore and a con--necting passageway affording communication be-- tween said groove andsaid. fluid inlet opening; said annular: extension being provided with:trans verse inlet ports on: diametrically opposite sides afiordingcommunication between saidgroove" and both pump chamber portions; a pairof outlet ports, in said annular extension; disposed rel atively to eachother in diametricallyoppositepassageways in. said housing each of whichaffords communication between difterent outlet ports. and a relatedoutlet openingwhereby; upon rotation of said rotor, fluid is drawn intothe:

alternate depressions successively in bothlpump;

chamber portions from said. single inlet opening and discharged underpressure in. substantiallyequal volumes from the different fluid; outletopenings.

8. A rotary fluid metering, pump comprising;

a. housing having a bore extending inwardly from one. endthereof, and a.fluidinlet opening, anda assent? pair ofi luid outlet openings; a cover"member.

atthe open end of said'housing andremovably' connected tothe latter,said cover member having an inwardly projecting annular extension snumyfitting the wall of the bore to provide with the: bottom of the'bore an.enclosed pump chami-j bar; a rotor rotatably disposed in said pumpchamber and having a non-circular peripheral; wall in the form ofalternate ridges and d:epressions so positioned relatively that the same(Ii men-slop prevails between all diametrically oppo site points on saidperipheral wall when passing: through; the axis of rotation ofsaidrotor, said ridges'be-ing rotatably engageable with the inner iperipheral wall of said extension and the alter-- nate depressions beingof substantially equal vol-- umetric' capacities, said rotor beingfurther provided with an axially disposed driving sha-ft ro"- tatablymounted in-said housing at the opposite sidefrom said cover; a bladeslidably bu-t nomrotatably mounted in said cover member and having itsopposite ends engag'eable diemetrically opposite sides of the peripheralwall of: said rotor for-effecting reciprocation of said blade; theopposite ends of said blade dividing said pump chamber into separatenon-coinmunieatingv portions; a continuous groove formed" on the: innerperipheral wall of said housing bore and normally closed on its innerside" by said annuiar extension; a pair of inlet ports in said annularextension, disposed rel-ati-vely to each other in diametrically oppositerelation "on oppo site sides of and inclos'e proximity to the respective ends-of said blade toafford co'mmumcation" between'said groove anddifferent pump chamber" portions an inlet passageway in said housingaffording communication between said single inlet opening said-groove; apairof outlet ports i'rr' said annular extension, disposedrelatively' toeach other diametrically opposite relation on opposite sides of and inclose proximity to the respective ends or said blade to afford communi:cationdifferent pump chamber portions, the: adjacent ports in eachpumpchamber por tion being spaced apart relatively to each other" a greaterdistance than the angular spacing of charged underpressure insubstantially equal volumes from the difierent fluid outlet openings;and power means o-peratively connected to. the

outer" end of said shaft for imparting rotation thereto;

9. Arotary fluid metering pump comprising; a"

housing having a circular" bore extending inwardly. from" one endthereof, an opening of rela tively smaller diameter than said boredisposed in axial alignmentwith said bore and communieating therewithyacover member at the boreend of said housing for normally closing thebore and removably connected to said housing, said cover member having asingle fluid inlet openinganda:

pair of fluid outlet openings; bearing material; in-

cluding a circular portion fitting snugly in said" I bore. and havin astem integral therewith, said stem being of smaller diameter than saidcircular portion and disposed in said communicating openings, saidcircular portion having a pump chamber bore: extending axiallyinwardfrom its-outer end; an:- opening of relatively smaller diameterthan said pump chamber bore extending centrally through said stem andcommunicating with said pump chamber bore; a rotor rotatably disposed insaid pump chamber bore and having an axially projecting stub shaftintegral therewith and of relatively smaller diameter rotatably mountedin the opening in said stem, the free end of said shaft being adaptedfor driving connection with a power means, the peripheral wall of saidrotor being in the form of ridges extending longitudinally thereof andsubstantially equally spaced apart relatively in angular relation andintervening depressions of small but substantially equal volumetriccapacity, the ridges being rotatably engageable with the innerperipheral wall of said pump chamber bore; slots transversely alignedwith each other on the cover end of said circular portion, a pair ofthin blades slidably but non-rotatablymounted in said slots and havingtheir inner ends engageable with diametrically opposite sides of theperipheral wall of said rotor for effecting reciprocation of said bladesand dividing said pump chamber into separate non-communicating portions;a marginal groove formed at the cover end of and on the outer peripheralwall of said circular portion, a looped resilient pre-loaded memberdisposed for free movement in said marginal groove, said looped memberbeing operatively connected to the outer ends of said blades foreffecting unitary movement of said blades without fiexure of said memberbut adapted to maintain engagement between said blades and rotorperipheral wall to compensate for slight error of contour in the latterwith minimum flexure; a pair of substantially identical inlet ports insaid circular portion disposed relatively to each other in diametricallyopposite relation on opposite sides of and in close proximity to therespective blades to afford communication with diflerent pump chamberportions; a peripheral groove of substantially uniform section formed atthe inner end of said circular portion; a pair of substantiallyidentical inlet passageways diametrically disposed with respect to eachother in said circular portion having their inner ends communicatingrespectively with the adjacent inlet port and their outer ends in commoncommunication with said peripheral groove; an inlet passageway in saidhousing having its inner end communicating with said peripheral grooveand its outer end communicating with the inlet opening on said covermember; a pair of substantially identical outlet ports in said circularportion disposed relatively to each other in diametrically oppositerelation on opposite sides of and in close proximity to the respectiveblades to afford communication with different pump chamber portions, theadjacent ports in each pump chamber portion being spaced apartrelatively to each other a greater distance than the angular spacing ofthe ridges on said rotor; and substantially identical outlet passagewaysin said pump, each of which has its inner end communicating withdifferent but adjacent outlet ports and its outer end communicating withdifierent but adjacent outlet openings in said cover member, whereby,upon rotation of said rotor, fluid is drawn into the interveningdepressions successively in both pump chamber portions from the singlefluid inlet opening and discharged under pressure in substantially equalvolumes from the difierent fluid outlet openings.

7 10. A rotary fluid metering pump comprising; a housing having a boreextending inwardly from one end thereof a cover member atthe. bore end16 of saidhousing fornormally closing the bore and removably connectedto said housing, said cover member having a single fluid inlet openingand a pair of fluid outlet openings; bearing material, including a'circular portion snugly fitting within said housing bore and having apump chamber bore extending axially inward from its outer end;' a rotorrotatably disposed concentrically in said pump chamber bore and havingan axially projecting shaft rotatably mounted in said housing; theperipheral wall of said rotor being in the form of ridges extendinglongitudinally thereof and substantially equally spaced apart relativelyin angular relation and intervening depressions of smallbutsubstantially equal volumetric capacity, the ridges bein rotatablyengageable with the inner peripheral wall of said pump chamber bore;slots transversely aligned with each other on the cover end of saidcircular portion, a pair of thin blades slidably but nonrotatablymounted in said slots and havin their inner ends engageable withdiametrically opposite sides of the peripheral wall of said rotor foreffecting reciprocation of said blades and dividing said pump chamberinto separate non-communicating portions; a marginal groove formed atthe cover end of and on the outer peripheral wall of said circularportion, a looped resilient pre-loaded member disposed for free movementin said marginal groove, said looped member being operatively connectedto the outer ends of said blades for effecting unitary movement of saidblade without fiexure of said member but adapted to maintain engagementbetween said blades and rotor pheriph'eral wall to compensate for slighterror of contour in the latter with minimum flexure; a pair ofsubstantially identical inlet ports of arcuate shape in cross sectiondisposed relatively to each other in diametrically opposite relation andformed on the inner peripheral wall of and extending for the depth ofsaid pump chamber bore, the inlet ports being positioned on oppositesides of and in close proximity to the respective blades to affordcommunication with different pump chamber portions; a peripheral grooveof substantially uniform section formed at the inner end of saidcircular portion, a. pair of substantially identical inlet passagewaysin said insert having their inner ends communicating respectively withthe adjacent inlet inner peripheral wall of and extending for the depthof said pump chamber bore, the outlet ports being positioned on oppositesides of and in close proximity to the respective blades to afiordcommunication with different pump chamber portions, the adjacent portsin each pump chamber portion being spaced apart relatively to each othera greater distance than the angular spacing of the ridges on said rotor;and substantially identical outlet passageways in said pump, each ofwhich has its inner end communicating with different but adjacent outletports and its outer end communicating with different but adjacent outletopenings in said cover member, whereby, upon rotation of said rotor,fluid is drawn into the intervening depressions successively in both 17pump chamber portions from said single fluid inlet opening anddischarged under pressure in substantially equal volumes from thedifferent fluid outlet openings.

11. A rotary fluid metering pump comprising: a-housing having a pumpchamber therein, a single fluid inlet opening, and a pair of fluidoutlet openings; a rotor rotatably disposed in said pump chamber andhavin a non-circular peripheral wall in the form of a three-lobe cam,the peaks of the cam being equally spaced apart about the axis of saidrotor and rotatably engageable with the inner peripheral wall of saidpump chamber, the depressions intervening between said peaks being ofsubstantially equal volumetric capacities, the peaks and depressionsbein so positioned relatively to each other that the same dimensionprevails between alldiametrically opposite points on said peripheralwall when passing through the axis of rotation of said rotor, said rotorhaving an axially projecting stub shaft of relatively smaller diameterthan said rotor rotatabl-y mounted in said housing, the inner face ofsaid rotor and bottom of said pump chamber being engageable with eachother to provide a fluid tight seal effected by fluid pressure, the freeend or said shaft being adapted for driving connection with a powermeans; slots transversely aligned with each other in. said housingadjacent said pump chamber, a pair of thin blades slidably butnon-rotatably mounted in said slots and havmg their inner endsengageable with diametrically opposite sides of the peripheral wall" ofsaid rotor for efiecting reciprocation of said blades and dividing saidpump chamber into separate non-communicating portions; resilientpre-loaded means; operatively connected to the outer ends of said bladesfor exerting a yieldable pressure to maintain; engagement between saidblades and rotor peripheral wall regardless of error of contour in thelatter; a pair of inlet ports in said housing disposed relatively toeach other in diametrically opposite relation on opposite sides of andin close proximity to the respective blades to afford. communicationwith differa en-t pump chamber portions; a continuous groove formed saidhousing, a pairof inlet passageways in said housing having their innerends communicating respectively with the adjacent inlet port and theirouter ends in. common communication with said continuous groove; aninlet passageway in said housing having its inner end communicating withsaid groove and its outer endv communicating with said single inletopenings; a pair of outlet ports in said housing disposed relatively toeach other in diametrically opposite relation on opposite sides of andin close proximity to the respective blades to aiford communication withdifferent pump chamber portions; the adjacent ports in each pump chamberportion being spaced apart relatively to each other a greater distancethan the angular spacing. of the ridges on said rotor; and outletpassageways in said housing, each of which has its inner endcommunicating with difierent but adjacent. outlet. ports and the outerend communieating with d-ifierent but adjacent outlet openings of thepair in said housing whereby, upon rotation of said rotor, fluid fromsaid single inlet opening, is drawn into the intervening depressionssuccessively into each pump chamber portion and discharged underpressure in substantially equal volumes from the different outletopenings.

12. A. rotary fluid metering pump comprising: a housing having a boretherein, a single fluid in 18 let opening, and a pair of fluid outletopenings; a removable insert snugly fitting within said housing bore andhaving a pump chamber bore eX- tending axially inward from one end ofsaid insert; a rotor rotatably disposed in said pump chamber bore andhaving a non-circular peripheral wall in the form of a three-lobe cam,the peaks of the cam being equally spaced apart about the axis of saidrotor and rotatably errgageable with the inner peripheral Wall of saidpump chamber bore, the depressions intervening between said peaks beingof substantially equal volumetric capacities; the peaks and depressionsbeing so positioned relatively to each other that the same dimensionprevails between all diametrically opposite points on said peripheralwall when passing through the axis of rotation of said rotor; said rotorhaving an axially projecting stub shaft rotatably mounted in saidhousing, the free end of said shaft being adapted for driving connectionwith a power means; slots transversely aligned. with each other in saidinsert adjacent said pump chamber bore, a pair of thin blades slidablybut non-rotatably mounted in said slots and having their inner endsengageable with diametrically opposite sides of the pe-- ripheral wallof said .rotor for effecting reciprocation of said blades and dividingsaid pump chamber bore into separate non-communicating portions;resilient pro-loaded means operatively connected to the outer ends ofsaid blades for ex-- erting a yieldable pressure to maintain engagementbetween said blades and rotor peripheral wall. regardless of error ofcontour'in the latter; a pair of inlet ports in said insert disposedrelatively to each other in diametrically opposite relation on oppositesides'of and in close proximity to. said blades to afford communicationwith different pump chamber portions; a continuous groove formed in saidinsert, a pair of inlet passageways in said insert having their innerends communicatingrespectively with the adjacent inlet port and theirouter ends in common communication with said continuous groove; an inletpassageway in said. housing having its inner end communicating with saidgroove and its outer end communicating with said single inlet opening; apair of outlet ports in said insert disposed relatively to each other indiametrically opposite relation on opposite sides of and in closeproximity to said blades'to afford communication with,

difierent pump chamber portions; the adjacent ports in each pump chamberportion being spaced apart relatively to each other a greater distancethan the angular spacing of the ridges on said tion and discharged underpressure in substantially equal volumes from the different outletopenings.

13;, A rotary fluid metering pump comprising:- a housing having a boretherein, a single fluid" inlet opening, anda pair of fluid outletopenings; a removable insert snugly fitted Within sai'dhou'sing bore andhaving a pump chamber bore extending axially inward from one end of saidin-- sort; a rotor rotatably disposed in said pump chamber bore andhaving a, non-circular periph--' 19 eral wall i'n the form of athree-lobe cam, the peaks of the cam being equally spaced apart aboutthe axis of "said rotor and rotatably engageable with the innerperipheral wall of said pump chamber bore, the depressions interveningbetween said peaks being of substantially equal vo-lumetric capacities;the peaks and depressions being so positioned relatively to each otherthat the same dimension prevails between all diametrically oppositepoints on "said peripheral wall when passing through the axis ofrotation of said rotor; said rotor having ah axially projecting stubshaft rotatably mounted in said housing, the free end of said shaftbeing adapted for driving connection with a power means; slotstransversely aligned with each other in said insert adjacent said pumpchamber bore, a pair of thin blades slidably but non-rotatably mountedin said slots and having their inner ends engageable with diametricallyopposite sides of the peripheral wall of said rotor for effectingreciprocation of said blades and dividing said pump chamber bore intoseparate non-communicating portions; a marginal groove formed at theouter end of said insort, a looped resilient pre-loaded member disposedfor free movement in said marginal groove, saidlooped member beingoperatively connected to the outer ends of said blades for exerting ayieldable pressure to maintain engagement between said blades and rotorperipheral wall when error of contour exists in the latter; a pair ofinlet ports in said insert disposed relatively to each other indiametrically opposite relation on opposite sides of and in closeproximity to the respective blades to afiord communication withdifferent pump chamber portions; a continuous groove formed in saidinsert, a pair of inlet passageways in said insert having their innerends communicating respectively with the adjacent inlet port andtheir-outer ends in common communication withvsaid continuous groove; aninlet passageway in said housing having its inner end communicating withsaid groove and its outer end communicating with said single inletopening; a pair of outlet ports in said insert disposed relativelyv toeach other in diametrically opposite relation on opposite sides of andin close proximity to the respective blades to afford communicationwith, different pump chamber portions; the adjacent ports in each pumpchamber portion being spaced apart relatively a greater distance thanthe angular spacing of the ridges on said rotor; and outlet passagewaysin said pump, each of which has its inner end communicating withdifferent but adjacent outlet ports and the outer end communicating withdifferent but adjacent outlet openings of the pair in said housingwhereby, upon rotation of said rotor, fluid from said single inletopening, is drawn into the intervening depressions successively intoeach pump chamber portion and discharged under pressure in substantiallyequal volumes from the different outlet openings.

14. A rotary fluid metering pump comprising: a housing having a pumpchamber bore extending inwardly from one end thereof; a cover member atthe bore end of said housing for normally closing the bore and removablyconnected to said housing, said cover member having a single fluid inletopening and a pair of fluid outlet openings; a rotor rotatably disposedin said pump chamber bore and having a non-circular peripheral wall inthe form of a three-lobe cam, the peaks of the cam being equally spacedapart about the axis of said rotor and rotatably engageable with 20' theinner peripheral wall of said pump chamber bore, the depressionsintervening between said peaks being of substantially equal volumetriccapacities; the peaks and depressions being so p0- sitioned relativelythat the same dimension prevails between all diametrically oppositepoints on said peripheral Wall when passing through the axis of rotationof said rotor, said rotor having an axially projecting stub shaft ofrelatively smaller diameter than said rotor rotatably mounted in saidhousing, the inner face of said rotor and bottom of said pump chamberbore being engageable with each other to provide a fluid tight sealeffected by fluid pressure, the free end of said shaft being adapted fordriving connection with a power means; slots transversely aligned witheach other in said housing adjacent said pump chamber bore, a pair ofthin blades slidably but non-rotatably mounted in said slots and havingtheir inner ends engageable with diametrically opposite sides of theperipheral wall of said rotor for effecting reciprocation of said bladesand dividing said pump chamber bore into sepa-' rate non-communicatingportions; resilient preloaded means operatively connected to the outerends of said blades for exerting a yieldable pressure to maintainengagement between said blades and rotor peripheral wall regardless oferror in the latter; a pair of inlet ports in said housing disposedrelatively to each other in diametrically opposite relation on oppositesides of and in close proximity to said blades to afford communicationwith difierent pump chamber portions; a continuous groove formed in saidpump, a pair of inlet passageways in said pump having their inner endscommunicating respectively with the adjacent inlet port and their outerends in common communication with said continuous groove; an inletpassageway in said housing having its inner end communicating with saidgroove and its outer end communicating with said single inlet opening; apair of outlet ports in said pump disposed relatively to each other indiametrically opposite relation on opposite sides of and in closeproximity to said blades to afford communication with diiferent pumpchamber portions; the adjacent ports in each pump chamber portion beingspaced apart relatively to each other a greater distance than theangular spacing of the ridges on said rotor; and outlet passageways insaid pump, each of which has its inner end communicating with differentbut adjacent outlet ports and the outer end communicating withdifierent' but adjacent outlet openings of the pair in said covermember, whereby, upon rotation of said rotor, fluid from said singleinlet opening, is drawn into the intervening depressions successivelyinto each pump chamber portion and discharged under pressure insubstantially equal volumes from the difierent outlet openings.

15. A rotary fluid metering pump comprising: a housing having a boreextending inwardly from one end thereof; a cover member at the bore endof said housing for normally closing the bore and removably connected tosaid housing, said cover member having a single fluid inlet opening anda pair of fluid outlet openings; a removable insert snugly fittingwithin said housing bore and havin a pump chamber bore extending axiallyinward from one end of said insert; a rotor rotatably disposed in saidpump chamber bore and having a non-circular peripheral wall in the formof a three-lobe cam, the peaks of the cam being equally spaced apartabout the axis of said rotor and rotatably engageable with the innerperipheral wall of said pump chamber bore, the depressions interveningbetween said peaks being of substantially equal volumetric capacities;the peaks and depressions being so positioned relatively to each otherthat the same dimension prevails between all diametrically oppositepoints on said peripheral wall when passing through the axis of rotationof said rotor; said rotor having an axially projecting stub shaftrotatably mounted in said housing, thevfree end of said shaft beingadapted for driving connection with a power means; slots trans verselyaligned with each other in said insert adjacent said pump chamber bore,a pair of thin blades slidably but non-rotatably mounted in said slotsand having their inner ends engageable with diametrically opposite sidesof the peripheral wall of said rotor for effecting reciprocation of saidblades and dividing said pump chamber bore into separatenon-communicating portions; resilient pre-loadied means operativelyconnected to the outer ends of said blades for exerting a yieldablepressure to maintain engagement between said blades and rotor peripheralwall regardless of error of contour in the latter; a pair of inlet portsin said insert disposed relatively to each other in diametricallyopposite relationon opposite sides of and in close proximity to therespective blades to afiord communication with d-ifierentpump chamberportions; a continuous groove formed in said insert, a pair of inletpassageways insaid insert having their inner ends communicatingrespectively with the adjacent inlet and their outer ends in" commoncommunication with said continuous groove; an inlet passageway in saidhousing having its inner end communicating with said groove and itsouter end communicating with said single inlet opening; a pair of outletports insaid insert disposed relatively to each other in diametricallyopposite relation on opposite sides of and in close proximity to therespective blades to afford communication with different pump chamberportions; the adjacent ports in each pump chamber portion being spacedapart relatively a greater distance than the angular spacing of theridges on said rotor; and outlet passageways, each of which has itsinner end communicating with diff erentbut adjacent outlet ports and theouter ends of said passageways communicating with different but adjacentoutlet openings of the pair in said cover member, whereby, upon rotationof said rotor, fluid from said single inlet opening, is drawn into theintervening depressions successively into each pump chamber portion anddischarged under pressure in substantially equal volumes from thediiierent outlet openings.

16. A rotary fluid metering pump comprising: a housing having a boreextending inwardly from one end thereof; a cover member at the bore endof said housing for normally closing the bore and removably connected tosaid housing, said cover member having a single fluid inlet opening anda pair of fluid outlet openings; a removable insert snugly fittingwithin said housing bore and having a pump chamber bore extendingaxially inward from one end of said insert; a rotor rotatably disposedin said pump chamber bore and having a non-circular peripheral wall inthe form of a three-lobe cam, the peaks of the cam being equally spacedapart about the axis of said rotor and rotatably engageable with theinner peripheral wall of said pump chamber bore, the depressionsintervening between said peaks being of substantially equal volumetriccapacities; the peaks and depressions being so positioned relatively toeach other that the same dimension prevails between all diametricallyopposite points on said peripheral wall whenpassing through the axis otrotation of said rotor; said rotor having an axially projecting stubshaft rotatably mounted in said housing, the free end of said shaftbeing adapted for driving connection with a power means a fluid sealabout said shaft and mounted in said housing a pair of thin bladesslidably but nonrotatably mounted in transversely aligned slots in saidinsert adjacent said pump chamber bore and having their inner endsengageable at diametrically opposite sides ofthe peripheral wall of saidrotor for effecting reciprocation of said blades anddividing said pumpchamber bore into separatenoncommunicating portions; resilientpro-loadedmeans operatively connected to the outer ends of said bladesfor exerting a yieldable pressure to maintain engagement between saidblades and rotor peripheral wall regardless of error of contour in thelatter; a pair of inlet ports in said insert disposed relatively to eachother in diametri-. cally opposite relation on opposite sides of and inclose proximity to the respective blades toaff or'd communication withdifferent pump chamber portions; a continuous groove formed insaidinsert, a pair of inlet passageways in said insert having their innerends communicating respectively with the adjacent inlet port and theirouter ends in common communication with said continuous groove; an inletpassageway in said locusing having its inner end communicating with saidgroove and its outer end communicating with said single inlet openings;a pair of outlet ports in said insert disposed relatively to each otherin diametricall-y opposite relation on opposite sides or and in closeproximity to the respective blades to at ford communication withdifferent pump chamber portions the adjacent ports ineach pump cham herportion being: spaced apart relatively to each other a greater distancethan the angular spacing of the ridges on said rotor; and outletpassageways in said pump, each of which has its inner end communicatingwith different but adjacent outlet ports and the outer end communicatingwith difierent but adjacent outlet openings of the pair in said covermember, whereby, upon rotation of said rotor, fluid from said singleinlet opening, is drawn into the intervening depressions successivelyinto each pump chamber portion and discharged under pressure insubstantially equal volumes from the different outlet openings.

17. A rotary fluid metering pump comprising: a housing having a boreextending inwardly from one end thereof; a cover member at the bore endof said housing for normally closing the bore and removably connected tosaid housing, said cover member having a single fluid inlet opening anda pair of fluid outlet openings; a removable insert snugly fittingwithin said housing bore and having a pump chamber \bore extendingaxially inward from one end of said insert; a bushing member mounted insaid cover member and disposed in abutting relation with respect to theadjacent end of said insert for normally closing the outer end of saidpump chamber bore; a rotor rotatably disposed in said pump chamber boreand. having a non-circular peripheral wall in the form of a three-lobec'am, the peaks of the cam being equally spaced apart about the axis ofsaid rotor and rotatably engageable with the inner peripheral wall ofsaid pump chamber bore, the depressions intervening between said peaksbeing of substantially equal volumetric capacities; the peaks anddepressions being so positioned relatively to each other that the samedimension pres vails between all diametrically opposite points on saidperipheral wall when passing through the axis of rotation of said rotor;said rotor having an axially projecting stub shaft rotatably mounted insaid housing, the free end of said shaft being adapted for drivingconnection with a power means; transversely aligned slots in said insertadjacent said pump chamber bore, a pair of blades slidably butnon-rotatively mounted therein and having their inner ends engageablewith diametrically opposite sides of the v peripheral wall of said rotorfor effecting reciprocation of said blades and dividing said pumpchamber bore into separate non-communicating portions; resilientpre-loaded means operatively connected to the outer ends of said bladesfor exerting a yieldable pressure to maintain engagement between saidblades and rotor peripheral wall regardless of error of contour in thelatter; a pair of inlet ports in said insert disposed relatively to eachother in diametrically opposite relation on opposite sides of and inclose proximity to the respective blades to afford communication withdifi'erent pump chamber portions; a continuous groove formed in'saidinsert; a pair of inlet passageways in said insert having their innerends communicating respectively with the adjacent inlet port and theirouter ends in common communication with said groove; an inletpassage'way in said housing having its inner end communicating with saidgroove and its outer end communicating with said single inlet opening;apair of outlet ports in said insert disposed relatively to each otherin diametrically opposite relation on opposite sides of and in closeproximity to the respective blades to afford communication withdifferent pump chamber portions; the adjacent ports in each pump chamberportion beingspaced apart relatively to each other a greater distancethan the angular spacing of the ridges on said rotor; and outletpassageways in said bushing and cover members, each of which has itsinner end communicating with difierent but adjacent outlet ports and itsouter end communicating with different but adjacent outlet openings ofthe pair in said cover member, whereby, upon rotation of said rotor,fluid from said single inlet opening, is drawn into the interveningdepressions successively into each pump chamber portion and dischargedunder pressure in substantially equal volumes from the difierent outletopenings.

- JAMES P. JOHNSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 607,678 'Brainerd July 19, 1898763,525 Van Beresteyn June 28, 1904 791,919 Leid June 6, 1905 934,968Harman Sept. 21, 1909 1,054,729 i/vhittinghill et al. Mar. 4, 19131,607,180 Storv Nov. 16, 1926 1,938,869 Shimerda Dec. 12, 1933 1,996,620Ketterer Apr. 2, 1935 2,036,543 Ross Apr. 7, 1936 2,073,101 Fox Mar. 9,1937 2,191,172 Lisowski Feb. 20, 1940 2,204,073 Dodge June 11, 1940FOREIGN PATENTS Number Country Date 203,978 Great Britain Sept. 20, 1923383,538 Great Britain Nov. 17, 1932 401,243 Germany Aug. 29, 1924

